This invention relates to determining characteristic combinations in a production environment. Many products exist in different configurations, such as different colors, different sizes, different models, or combinations thereof. A product manufacturer is typically interested in producing a certain number of products of each configuration. A simplified example of a typical situation is as follows.
Assume that a car manufacturer produces cars of three colors; red, green and blue. During a given week, the manufacturer would like to produce a total of 10 cars that are as evenly distributed among the three colors as possible. If the total number of products to be produced in a given day is of the same or lesser order of magnitude as the number of combinations, or if the resulting characteristic combinations have to be represented as integers, problems can occur. For example, if the 10 cars are to be produced in five working days, the number of cars produced per day is two, and the manufacturer would have to produce ⅔ or 0.67 cars of each color per day, which is not possible.
In existing systems, this problem is typically solved by rounding the values up or down to the nearest integer. Thus, the production on day 1 is determined as follows. The desired 0.67 red cars is rounded up to 1.0 car. The difference between the produced number and the desired number, −0.33, is added to the 0.67 green cars to be produced, giving a total of 0.34 green cars. This number is rounded down to 0 green cars. The difference 0.34 is added to the 0.67 blue cars to be produced, giving a total of 1.01 blue cars. This number is rounded down to 1.0 blue cars. This yields a red car and a blue car on day 1. If the same method is repeated each working day, and at the end of the week, a total of 10 cars have been produced, five of which are red and five of which are blue. No green cars will be produced during the entire week. Even though 10 cars have been produced, the distribution among the three colors does not satisfy the original intentions to have the cars distributed as evenly as possible among the three different colors.
An alternative rounding algorithm rounds the value 0.67 for each color up to 1. However, the individual rounding results in a change of the total sum to 15 instead of 10, thereby exceeding the desired subtotals for each combination of characteristics. As can be seen, both the above-described rounding procedures are inconsistent, and the results are therefore often corrected manually after the initial result has been produced, which can be a very time consuming task, or may not even be possible when there are a large number of characteristics.
It should be noted that the problem described above is particularly prevalent for cases where the desired number of items is of the same order of magnitude as the total number of combinations. The two rounding procedures described above work better if the total value to be disaggregated is much larger than the number of combinations.